In Morality and Capitalism: A Dialogue on Freedom,David teaches about why capitalism is the only economic system to use if you are concerned about morality. He does this in an interesting way. Much of the book contains a dialogue between a wise teacher and an inquisitive student.
The book is great and I highly recommend it. It's not too long and you can get it for your e-reader for a reasonable price. (Right now it is $4.99.)
I don't want to give much away, but I can't resist putting in a few excerpts:
1. All people want to be free. Freedom is a universal human value. But we cannot be free if we are compelled by others. Consequently, if we want to be free, we should be moral.
2. Tyro: So, we should quit using the term "public property"?
Solon: No, Tyro. That would be impractical. It is fine to call certain land "public property," provided we understand that such property is not and cannot be owned "collectively".
3. Rational People have but one right, the right to be free of unjust compulsion of others.